Various mobile devices, also referred to herein a User Equipment (UE), can operate in wireless communication networks that provide high-speed data and/or voice communications. The wireless communication networks can implement circuit-switched (CS) and/or packet-switched (PS) communication protocols to provide various services. For example, a user device can operate in accordance with one or more radio technologies such as: Universal Terrestrial Radio Access (UTRA), Evolved UTRA (E-UTRA), Global System for Mobile Communications (GSM), Universal Mobile Telecommunication System (UMTS), and Long Term Evolution (LTE). Descriptions and specifications for UTRA, E-UTRA, GSM, UMTS and LTE protocols are available from the Third Generation Partnership Project (3GPP), which is a partnership that united telecommunications standards development organizations and provides their members with an environment to produce reports and specifications that define 3GPP technologies.
Evolved Packet Core (EPC) technology was developed based on the 3GPP core network architecture. In EPC, the user data and the signaling data are separated into the user plane and the control plane to allow a network operator to easily adapt and scale their networks. At a high level, EPC architecture includes four basic network elements: the Serving Gateway (SGW), the Packet Data Network Gateway (PDN GW or PGW), the Mobility Management Entity (MME), and the Home Subscriber Server (HSS). The EPC can be connected to external networks, which can include an Internet Protocol Multimedia Core Network Subsystem (IMS).
An IMS is generally configured to facilitate the use of Internet Protocol (IP) for packet communications, such as telephony, facsimile, email, Internet access, Web Service, Voice over IP (VoIP), instant messaging (IM), videoconference sessions, video on demand (VoD), and the like, over wired and/or wireless communication networks. Due to bandwidth used by many IMS applications, the communications with the UE is generally over 4G, LTE radio, or wife, or the like.
Similarly, Real-Time Communication in WEB-Browsers (WebRTC) is configured to provide browsers and mobile applications with real-time communications capabilities via simple application programming interfaces and certain communication protocols. WebRTC enables applications (via a browser) such as video conferencing, file transfer, chat, voice calling, video calling, messaging, or desktop sharing. A WebRTC gateway is configured to facilitate communication between a WebRTC OTT application and an IMS core network. A user device can run a WebRTC OTT application or an IMS OTT application.
Mobile devices and other UE typically have an operating system (OS) that controls the applications run on the device/UE. Additionally, the mobile device/UE will have over the top (OTT) applications, such as a phone application or text messaging application. Some of these OTT applications are IMS applications implemented as an IMS client on the mobile device/UE. As discussed in more detail below, the more recent versions of operating systems (e.g., iOS, Android) for mobile devices and other UE, will often suspend the OTT applications after a short period of time. This suspended state prevents IMS services from being possible, and result in missed calls and messages. Thus, it is desirable for mobile phones and other UE running IMS services on OTT applications to function as expected regardless of the operating systems suspending the OTT applications. Accordingly, improved communications systems and methods are desired.
It will be appreciated that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of illustrated embodiments of the present disclosure.